Lot link problems

[George Khouri]

Friends,
I upgraded from gnucash 2.4 to 2.6 on linux. Without looking into the 
new features, I continued using 2.6. After posting many invoices and 
payments, I realized there were all these lot link entries in AR, which 
had never been there before.  I thought my partner had made some wrong 
entries, so I changed many of the lot links to invoices in the AR 
register. My (very) bad. Is there a way to reverse what I've done? Or, 
shall I ask, "what is the proper way to reverse what I've done?" I can't 
really go back to a backup, since much data entry has followed. I've 
searched and read the mailing list entries and haven't quite found the 
answer.
Is it a matter of (in some order):
1.  Delete the lot link entry in AR,
2. Find the associated payments with the relevant invoices and reassign 
them to their proper invoices?

Do I need to unpost the invoices first, or ever?
Do I need to delete the payments?

Also, in the  menu Actions->View Lots...  dialog, clicking on an open 
invoice in the list titled "Lots in this account" would show the item 
detail in a window below that in the same dialog yesterday. Now the 
lower window(s) in the dialog are gone. No upgrades/updates here since 
then. Is this a bug?  I tried deleting my preference in ~/.gnucash but 
the dialog has changed since yesterday.
BTW, is there documentation on what this dialog does? I couldn't find any.

Thanks for any help,
George Khouri